# #303a91

A color — cool, modern. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#303a91`
- RGB: rgb(48, 58, 145)
- HSL: hsl(234, 50%, 38%)
- OKLCH: oklch(0.395 0.142 273)
- Relative luminance: 0.057
- Nearest named color: Bluebell (#333399, Δ 2.099) — https://brandsweets.com/colors/bluebell
- Moods: cool, modern
- Page: https://brandsweets.com/colors/303a91

## Tints & shades

- Tints (toward white): #3843a8, #404dbf, #5762c7, #6e77cf, #858dd6, #9ca2de, #b3b8e6, #c9cded, #e0e2f5, #f7f8fc
- Shades (toward black): #2d3686, #282f77, #242b6b, #1f255c, #1b2050, #171c45, #121536, #0e112a, #090b1b, #05060f

## Harmonies

- Complementary: #918830
- Analogous: #306b91, #573091
- Triadic: #91303a, #3a9130
- Split-complementary: #915730, #6b9130
- Tetradic: #91306b, #918830, #309157

## Colors that go with #303a91

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Charcoal** #36454f [role, pool] — Charcoal is the text near-black for #303a91: softer than #000 and cool enough to feel like part of the same palette. Seen in: dbt Labs (https://brandsweets.com/colors/brands/getdbt-com), Tumblr (https://brandsweets.com/colors/brands/tumblr-com), Harbour (https://brandsweets.com/palettes/cool#harbour), Amazon (https://brandsweets.com/colors/brands/amazon-com). — https://brandsweets.com/colors/charcoal
- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #303a91 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Intel (https://brandsweets.com/colors/brands/intel-com), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #303a91's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Glacier (https://brandsweets.com/palettes/cool#glacier), Hershey's (https://brandsweets.com/colors/brands/hersheys-com), FedEx (https://brandsweets.com/colors/brands/fedex-com). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 6 real palettes, including Procter & Gamble's brand system and CVS's brand system put Blue beside #303a91, as the supporting colour. Seen in: Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Tesco (https://brandsweets.com/colors/brands/tesco-com), Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com). — https://brandsweets.com/colors/blue
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #303a91: 4 real palettes, including Blue Mono and Peacock's brand system, as the supporting colour. Seen in: Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Peacock (https://brandsweets.com/colors/brands/peacocktv-com), Gopro (https://brandsweets.com/colors/brands/gopro-com), Coca-Cola (https://brandsweets.com/colors/brands/coca-cola-com). — https://brandsweets.com/colors/cornflowerblue
- **Crimson** #dc143c [pool] — Crimson is paired with #303a91 in 14 real palettes, including Walgreens's brand system and Casper Sleep's brand system, as the lead colour. Seen in: Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Marvel (https://brandsweets.com/colors/brands/marvel-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #303a91: 15 real palettes, including Warbyparker's brand system and Unilever's brand system, as the accent. Seen in: Warbyparker (https://brandsweets.com/colors/brands/warbyparker-com), Unilever (https://brandsweets.com/colors/brands/unilever-com), General Mills (https://brandsweets.com/colors/brands/generalmills-com), Hasbro (https://brandsweets.com/colors/brands/hasbro-com). — https://brandsweets.com/colors/denim
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #303a91: 5 real palettes, including Nintendo's brand system and Datadog's brand system, as the accent. Seen in: Nintendo (https://brandsweets.com/colors/brands/nintendo-com), Datadog (https://brandsweets.com/colors/brands/datadoghq-com), MLB (https://brandsweets.com/colors/brands/mlb-com), 3M (https://brandsweets.com/colors/brands/3m-com). — https://brandsweets.com/colors/firebrick

## Contrast (WCAG 2.x, as text)

- On white (#ffffff): 9.81:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.14:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #626dcb (4.57:1); AA: background → #b0b0b0 (4.53:1); AAA: text → #8890d7 (7.02:1); AAA: background → #dbdbdb (7.09:1)

## Fonts for this mood

- modern: https://brandsweets.com/fonts/mood/modern

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/303a91-9d9cc4-df8a4e-241f2d-e9eef1?lock=0&style=vibrant
(Humans lock/regenerate in the tool; the URL is the state — read `lock=` back to see what they kept.)

## Connect an agent

Point any MCP client at the BrandSweets colors endpoint for the same engine:

- Endpoint: https://mcp.brandsweets.com/colors/mcp
- Tools: `analyze_color` (e.g. `analyze_color({ color: "#303a91" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.